Systems and methods for broadband signal equalization

Abstract

An interference canceling subsystem for a bidirectional communications network includes an input interface configured to receive a first data signal from a first transceiver of the network, an output portion configured to receive a second data signal from a second transceiver of the network, a first signal path connecting the input interface to the output portion, a second signal path connecting the output portion to the input interface, and a first interference canceler disposed between the output portion and the input interface along the second signal path. The first signal path is configured to relay the first data signal from the input interface to the output portion. The interference canceler is configured to (i) relay the second data signal from the output portion to the input interface, and (ii) remove portions of the first data signal from the relayed second data signal prior to reaching the input interface.

The invention claimed is: 
     
       1. An equalization subsystem disposed along a transport medium between a first transceiver and a second transceiver, the subsystem comprising:
 a first interface in operable communication with the transport medium and configured to receive a first data signal from the first transceiver; 
 a second interface in operable communication with the transport medium and configured to receive a second data signal from the second transceiver; 
 an equalizer disposed between the first interface and the second interface; 
 a first amplifier disposed between the first interface and the equalizer and configured to amplify the second data signal from the equalizer to the first interface; and 
 a second amplifier disposed between the second interface and the equalizer and configured to amplify the first data signal from the equalizer to the second interface, 
 wherein the equalizer is configured to (i) remove first data portions of the first data signal from the second data signal prior to amplification of the second data signal by first amplifier, and (ii) remove second data portions of the second data signal from the first data signal prior to amplification of the first data signal by second amplifier. 
 
     
     
       2. The subsystem of  claim 1 , wherein the equalizer comprises a single equalizer configured for multiple-input/multiple-output operation. 
     
     
       3. The subsystem of  claim 1 , wherein (i) the first amplifier is disposed along a first signal path between the first interface and the equalizer, (ii) a second signal path connects the first interface with the equalizer separately from the first signal path, (iii) the second amplifier is disposed along a third signal path between the second interface and the equalizer, and (iv) a fourth signal path connects the second interface with the equalizer separately from the third signal path. 
     
     
       4. The subsystem of  claim 3 , wherein the second signal path carries the first data signal and the second data portions of the second data signal, and wherein the fourth signal path carries the second data signal and the first data portions of the first data signal. 
     
     
       5. The subsystem of  claim 3 , wherein the equalizer is further configured to extract (i) the first data signal from the second signal path for input to the second amplifier, and (ii) the second data signal from the fourth signal path for input to the first amplifier. 
     
     
       6. The subsystem of  claim 3 , wherein the first and second signal paths form a first loop between the first interface and the equalizer, and wherein the third and fourth signal paths form a second loop between the second interface and the equalizer. 
     
     
       7. The subsystem of  claim 1 , wherein the first transceiver is disposed within a hub of a bidirectional communications network. 
     
     
       8. The subsystem of  claim 7 , wherein the first transceiver includes a modem termination system (MTS). 
     
     
       9. The subsystem of  claim 8 , wherein the MTS includes one or more of a cable MTS (CMTS), an optical network terminal (ONT), an optical line terminal (OLT), a network termination unit, and a satellite termination unit. 
     
     
       10. The subsystem of  claim 7 , wherein the second transceiver includes a modem. 
     
     
       11. The subsystem of  claim 10 , wherein the modem includes one or more of a cable modem (CM), an optical network unit (ONU), a digital subscriber line (DSL) unit or modem, and a satellite modem. 
     
     
       12. The subsystem of  claim 7 , wherein the second transceiver includes a plurality of modems. 
     
     
       13. The subsystem of  claim 12 , wherein the second data signal includes an aggregated plurality of third data signals respectively transmitted from the plurality of modems. 
     
     
       14. The subsystem of  claim 12 , wherein the first data signal includes an orthogonal frequency division multiplexing (OFDM) digital transmission, and wherein the second data signal includes an orthogonal frequency division multiple access (OFDMA) digital transmission. 
     
     
       15. The subsystem of  claim 1 , wherein the transport medium is an optical transport medium. 
     
     
       16. The subsystem of  claim 15 , wherein the optical transport medium includes a single mode fiber (SMF). 
     
     
       17. The subsystem of  claim 1 , wherein the transport medium is an electrical radio frequency (RF) transport medium. 
     
     
       18. The subsystem of  claim 17 , wherein the electrical RF transport medium includes a coaxial cable. 
     
     
       19. The subsystem of  claim 1 , wherein the transport medium is wireless. 
     
     
       20. The subsystem of  claim 1 , wherein the first and second data signals conform to a communication protocol including at least one of a time division duplex (TDD) mode, a frequency division duplex (FDD) mode, and a full duplex (FDX) mode.